The present invention relates to a new and improved coupling arrangement for controlling the harnesses or the like in a weaving machine or loom for weaving a fabric in acccordance with a predetermined weaving program.
In its more particular aspects the present invention relates to a new and improved coupling arrangement for controlling the harnesses in a weaving machine for weaving a fabric in accordance with a predetermined weaving program, which coupling arrangement comprises an intermittently rotating drive shaft which contains at least one groove, a latch or latching element engageable with the groove and arranged at an eccentric which, in turn, is rotatably mounted upon the drive shaft, and a bracket which encloses the eccentric and which is provided at a connecting rod establishing a driving connection to the harnesses of the weaving machine or loom. The coupling arrangement further comprises locking means arranged at the eccentric for locking the latch into a coupling position with the drive shaft, and control means for controlling the latch and the harnesses in accordance with the weaving program for the fabric or cloth to be produced.
In an arrangement of the aforementioned type as known, for example, from European Patent Publication No. 0050160-A1, published Apr. 28, 1982, a locking lever is pivotably mounted to the eccentric and revolves with the eccentric so as to be alternatingly moved against two run-up surfaces which are arranged at the bracket at the connecting rod and which protrude into the travel path of a rearward or trailing end of the locking lever. By means of these run-up surfaces, the locking lever is pivoted twice into an unlocking position during each revolution of the eccentric. Consequently, the latch is also prepared for a decoupling operation twice per revolution, in particular even then when the latch is intended to remain in its coupled position for the next weft insertion of the weaving machine in accordance with the weaving program. In case that for whatever reason stronger shocks or vibrations occur in the weaving machine as, for example, also during shut down thereof precisely during this time interval when the latch is unlocked without subsequent decoupling of such latch, the latch may be unintentionally decoupled due to the temporary unlocking thereof, whereby operational malfunctions can occur.